I think most of it is Hodaka 250 SL but the tank came from a Yamaha DT250/400B looks like a yamaha, but it is a 2 stroke bike imho! on the tank you can see ....KA writing , visible here /vehicle_961058-Honda-XL-1974.html
I've revised my opinion, the snail cam chain adjusters and near vertical rear shocks make it a Hodaka 250ED Thunderdog, the mudguards and tail light are off something else (possibly 250SL) but the tank is definitely Yamaha DT250/400B.